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What Is the State Tree of Wyoming? History, Facts, & FAQ

plains cottonwood trees

Longtime Wyoming residents proudly boast of their state as being one of the most beautiful in the US, and with good reason. Wyoming features dramatic and diverse landscapes ranging from high elevation deserts, rugged mountains, prairie grasslands, and heavily wooded hills. It is also home to some of the tallest cottonwood tree species in America. Therefore, it’s no surprise that the state tree of Wyoming is the plains cottonwood.

The inspiration for proposing the plains cottonwood tree as the official state tree of Wyoming came from the discovery of a specimen. It measured about 50–55 feet tall. At the time, it was thought to be the largest cottonwood tree in the world.

In this article, we will discuss how plains cottonwood came to represent Wyoming as well as its features, significance, and how to identify the plains cottonwood tree.

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Origin & History of the Plains Cottonwood

The plains cottonwood is a member of the willow family. It is native throughout the central plains of Texas to Manitoba. This tree thrives in saturated soils, especially near creeks, ponds, and lakes. Even though they can survive in water, they can also do well in drier soils.

If it is planted near a home, some care should be provided. For instance, you should water, fertilize and kill any pests and insects that may hamper its development. Additionally, damaged or dying branches should be removed to reduce the tree’s susceptibility to diseases.

The greatest threats to plains cottonwood trees are drought and fire. This tree species is very vulnerable to fire. In fact, the largest cottonwood tree to be discovered in Wyoming died in a fire on May 1, 1955, after being struck by lightning. Even light burns will kill the saplings and seedlings. Fires that burn hotter can severely injure the bark, exposing the tree to decaying agents. Even though the tree is moderately drought tolerant, a long-term dry spell will inevitably lead to death.

How Was It Decided as the State Tree of Wyoming?

On January 18, 1947, the legislative activity to declare the plains cottonwood Wyoming’s official state tree began. State Representative Ken Byerly introduced House Bill No. 15 to the legislature. The House bill specifically proposed the plains cottonwood species to be the state tree.

In the bill, Byerly argued that Wyoming was home to the “largest cottonwood tree in the world,” making it a desirable selection to represent the state. The bill also stated that the tree would provide bountiful comfort and beauty to future generations of Wyomingites, and offer shade and shelter to livestock.

Just 9 days after its introduction, on January 27th, 1947, the bill was unanimously approved by the House of Representatives and forwarded to the Senate for further consideration. The senate was impressed by the bill and felt that it was proper and fitting that the plains cottonwood tree is designated as the state tree of Wyoming.

On February 1, 1947, the cottonwood tree (Populus balsamifera) was made the official state tree when the Governor signed House Bill No.15. The law designating the cottonwood tree as the official Wyoming state tree is found in the Wyoming Statutes, Title 8, Chapter 3, Section 8-3-106.

Amendment of the Bill

Just 14 years after cottonwood was declared the state tree of Wyoming, the state tree designation was revisited after it was determined that the cottonwood species specified in the bill was not the intended recipient of the official status. This is because the bill had incorrectly identified “Populus balsamifera” instead of the intended “Populus sargentii.

On January 21, 1961, the senate File No. 121 was introduced to correct the scientific name of the official state tree. The legislation, which was introduced by Senators Harvey Johnston and Norman Barlow, proposed a change to the state tree designation from Populus balsamifera to Populus sargentii.

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Why the Plains Cottonwood Was Chosen to Represent Wyoming

The plains cottonwood was chosen to represent Wyoming for two major reasons:

1. It Grows Easily and Quickly

The discovery of the largest plains cottonwood in Thermopolis, Wyoming heavily influenced the state’s decision to designate the tree as an official symbol. The tree was believed to be the perfect state tree because of its height and its huge thickness and the fact that it was the largest cottonwood species in America.

2. The Changing Weather in Wyoming Agreed With the Cottonwood

Since Wyoming experiences changing weather patterns, the state doesn’t have many wooded forests that you would expect in the more humid eastern parts of the United States. The plains cottonwood is one of the few tree species that can withstand the semi-arid climate, allowing the trees to grow and thrive.

This is perhaps why early pioneers in Wyoming began to plant the trees to create shade from the sweltering sun, causing them to increase in numbers across the state.

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Identification of the Plains Cottonwood

  • Leaves: The leaves of the plain’s cottonwood are triangle shaped with serrated edges. They are usually 3–6 inches long.
  • Flowers: The flowers appear during the spring season, right before the leaves appear. They are usually bright yellow and deciduous. Both the male and female flowers appear as pendulous catkins.
  • Fruits: The tree produces an abundance of cotton-like fruit with cottony seeds that mature over summer. The fruits measure 64 centimeters long and have three to four valved capsules. People often notice the fruit from its sweet smell wafting through the air.
  • Bark: The bark of this tree is smooth and is ash-gray or yellow-green when young. When fully mature, it takes on a grayer disposition with thick ridges and deep furrows.
  • Life span: Cottonwood has a very short lifespan compared to other native species. As with its cousins the willow trees, cottonwoods typically live for about 70 years. However, there have been reports of a plains cottonwood tree that is 120 years old.
  • Size: Even though cottonwoods may not live for long, they are fast-growing, so big plains cottonwood trees in Wyoming are a common sight. One of the largest cottonwoods discovered measures 31 feet in circumference and 132 feet in height. The branches spread up to 99 feet. This massive tree is found in Grundy County, Illinois.

Significance of the Plains Cottonwood Tree to Wyoming

The wood from the plain’s cottonwood is relatively light, making it an important material for construction for the early European and American Indian settlers. Because of its abundance in the state of Wyoming, cottonwood trees were used to build houses and barns.

Occasionally, large cottonwoods were cut down and burned to make canoes. The people also ate the sweet inner bark of the young cottonwood sprouts during spring. They also fed their horses cottonwood branches. In addition, the sacred pole used in the ceremonies performed by Omaha Indians is made from Cottonwood. They also made dye from the leaves of the tree.

Today, cottonwood is mostly used for pulp and to make lightweight furniture. Plains cottonwood trees are also used as a windbreak species. However, this is discouraged due to the tree’s short life expectancy.

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The Plains cottonwood tree is the state tree of Wyoming. It was first selected by Wyoming’s Legislature to represent the state in February 1947. However, in 1961 the legislature amended the statute to clarify the scientific name as Populus deltoides.

The plains cottonwood tree was an ideal option because it agrees with the state’s semi-arid climate. The tree was also selected because of a discovery of the species in the state, which was, by then, the largest cottonwood species in America.

The tree can grow to heights of about 55 feet. Unfortunately, it has a short lifespan. Today, the tree is used to make lightweight furniture and as a windbreak species. The greatest threats to the tree’s existence are fire and drought. All things considered, the tree is robust and majestic and deserves the state tree title.

Featured Image Credit: Ann Cantelow, Shutterstock


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